V C 181 ) Agate. The foflils known by the name Agate are all com- pound, therefore are more properly objects of gsog- nofie than orydlognofie. Werner, however, has placed them in his ory&ognoftic fyftem as an appen dix to the fpecies chalcedony, probably on account of their occurring in inconfiderable quantity, and from chalcedony forming their principal conflituent part. They are compounded of chalcedony, carnelian, jafper, hornftone, quartz, heliotrope, amethyft, indu rated lithomarga, and opal, lhefe different foflils do not occur in every agate, molt commonly only two or three, a circumftance which affords us a bafis for an arrangement of them according to their con- ftituent parts. Such an arrangement, however, Would be very difficultly accomplifhed ; hence Wer ner has preferred the eafier method of difpofing them According to their colour delineations. 1 hefe de- lin eations are formed by the manner of junction of the different foflils. i The following are the different kinds of agate mentioned by Werner : i. Fortification agate. 2. Landfcape agate. 3. Ribbon agate. 4. Mois agate. 5* Tube agate. 6. Clouded agate. 7. Zoned agate. 8. Star agate. 9. Fragment agate. 10. Punctat ed